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201.
Alcoholism is a significant public health problem. A picture of the genetic architecture underlying alcohol-related phenotypes
is emerging from genome-wide association studies and work on genetically tractable model organisms. 相似文献
202.
Antoine?StierEmail author Sophie?Reichert Sylvie?Massemin Pierre?Bize Fran?ois?Criscuolo 《Frontiers in zoology》2012,9(1):37
Background
One central concept in evolutionary ecology is that current and residual reproductive values are negatively linked by the so-called cost of reproduction. Previous studies examining the nature of this cost suggested a possible involvement of oxidative stress resulting from the imbalance between pro- and anti-oxidant processes. Still, data remain conflictory probably because, although oxidative damage increases during reproduction, high systemic levels of oxidative stress might also constrain parental investment in reproduction. Here, we investigated variation in oxidative balance (i.e. oxidative damage and antioxidant defences) over the course of reproduction by comparing female laboratory mice rearing or not pups.Results
A significant increase in oxidative damage over time was only observed in females caring for offspring, whereas antioxidant defences increased over time regardless of reproductive status. Interestingly, oxidative damage measured prior to reproduction was negatively associated with litter size at birth (constraint), whereas damage measured after reproduction was positively related to litter size at weaning (cost).Conclusions
Globally, our correlative results and the review of literature describing the links between reproduction and oxidative stress underline the importance of timing/dynamics when studying and interpreting oxidative balance in relation to reproduction. Our study highlights the duality (constraint and cost) of oxidative stress in life-history trade-offs, thus supporting the theory that oxidative stress plays a key role in life-history evolution.203.
de Morais MG da Cruz Reichert C Dalcanton F Durante AJ Marins LF Costa JA 《Zeitschrift für Naturforschung. C, Journal of biosciences》2008,63(1-2):144-150
A filamentous microorganism, morphologically similar to the cyanobacterium Arthrospira, was isolated from Mangueira Lagoon in Brazil, from which Arthrospira has not previously been isolated. Random amplified polymorphic DNA (RAPD) comparison with the standard Arthrospira platensis strains LEB 52 and Paracas indicated that the organism isolated was an Arthrospira isolate, which we denominated strain LEB 18. The RAPD analysis showed conserved sequences which indicated that the three strains belonged to the same genus, and were all Arthrospira species, but there were sufficient differences between them suggesting that they were separate strains. The strain LEB 18 was cultivated in undiluted Zarrouk medium and in 60% and 20% (v/v) Zarrouk medium diluted with sterilized Mangueira Lagoon water (MLW) using illuminance rates of 32.5, 45.5 and 58.5 micromol m(-2) s(-1) according to a complete 32 factorial design with a triplicate central point. The strains LEB 52 and Paracas were cultived in the conditions central point. Our new isolate produced the highest specific growth rate (Umax = 0.22 d(-1)) in 60% Zarrouk medium diluted with MLW and illuminated with 58.5 micromol m(-2) s(-1) and the highest protein content (86.0% w/w). 相似文献
204.
We prepared amyloid-like fibrinogen (Fg) fibrils at pH 2.0 in the absence of thrombin; furthermore, we prepared uniform 2-D Fg fibril networks on a hydrophilic mica matrix. We found that several experimental parameters, such as concentration, pH value, and ionic strength, strongly affected the formation of Fg fibrils as well as fibril networks. Biomimetic mineralization was conducted on the Fg fibrils and 2-D Fg fibril networks in 1.5x simulated body fluid (SBF) for different periods of time. The present results may lead to a fundamental understanding of possible mechanisms for the pH-mediated self assembly of Fg molecules and the formation of Fg fibrils and fibril networks in the absence of thrombin and provide a feasible strategy that may enable the design and fabrication of new functional biomaterials based on self-assembled protein fibrils. 相似文献
205.
At the rocky island of Helgoland (North Sea), the distribution and abundances of intertidal communities were assessed and
the effects of wave exposure and tidal height on the spatial distribution patterns of the communities were evaluated. Macroalgae
and invertebrates were sampled quantitatively along line transects in three intertidal locations, a semi-exposed, an exposed
and a sheltered one. The semi-exposed location was characterised by (1) Ulva spp. at the high intertidal (Ulva-community), (2) mussels and periwinkles at the mid intertidal (Mytilus-community) and (3) Corallina officinalis and mainly the large brown alga Fucus serratus at the low intertidal (Fucus-community). The exposed location encompassed the mid and low intertidal; at both zones the Fucus-community occurred. The sheltered location was characterised by (1) barnacles (Balanus-community) and (2) bryozoans, hydrozoans and mainly the large brown alga Ascophyllum nodosum (Ascophyllum-community). At the semi-exposed, but not at the exposed location the communities changed with the intertidal position. A
relationship between wave exposure and the occurrence of specific communities was shown for the sheltered location; in contrast,
communities of the semi-exposed and the exposed location appear to be little influenced by wave exposure directly. The community
concept and the potential causes of distribution patterns of the defined communities are discussed and suggestions for a future
monitoring are given. Variations in the communities at different spatial scales speak in favour of a multiple scale sampling
design to monitor changes in the intertidal communities at Helgoland.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
206.
207.
Isao Sakurada Toshiya Endo Katsuyoshi Hikita Tomokazu Hirabayashi Yoshitaka Hosaka Yutaka Kato Yoshitaka Maeda Shigeki Matsumoto Takashi Mizuno Hiroshi Nagasue Teruyuki Nishimura Shunsuke Shimada Mikihiko Shinozaki Keiko Taguchi Katsutoshi Takeuchi Tooru Yokoyama Alan Hruza Paul Reichert Shoji Furusako 《Bioorganic & medicinal chemistry letters》2017,27(11):2622-2628
Using structure based drug design, novel aminobenzisoxazoles as coagulation factor IXa inhibitors were designed and synthesized. Highly selective inhibition of FIXa over FXa was demonstrated. Anticoagulation profile of selected compounds was evaluated by aPTT and PT tests. In vitro ADMET and pharmacokinetic (PK) profiles were also evaluated. 相似文献
208.
209.
C L Ritter W F Prigge M A Reichert D Malejka-Giganti 《Canadian journal of physiology and pharmacology》2001,79(6):519-532
Altered cytochrome P450-catalyzed metabolism of 17beta-estradiol (E2) and estrone (E1) in the liver and (or) extrahepatic tissues may affect estrogen-sensitive tumorigenesis. We examined the effects of oral treatments of (i) indole-3-carbinol (13C) at 250 or 500 mg/kg or beta-naphthoflavone (beta-NF) at 40 mg/kg of body weight (bw)/day from 51 to 54 days of age (acute regimen), and (ii) 13C at 250 mg/kg or beta-NF at 20 mg/kg bw given 3x/week from 10 to 22 weeks of age (chronic regimen) in female Sprague-Dawley rats. We determined the effects of these treatments on the P450 content and P450 (CYP)-specific activities in the liver, P450-dependent metabolism of E2 and E1 by the liver and mammary gland, and interconversion of E1 and E2 catalyzed by 17beta-hydroxysteroid dehydrogenase (17beta-HSD) in these tissues and malignant mammary tumors. 13C at the two levels of acute regimen elicited similar responses. Acute and chronic treatments with 13C, but not beta-NF, increased P450 content approximately 2-fold. 13C, and to a lesser extent beta-NF, increased CYP1A1 and CYP1A2 probe activities in liver up to 117- and 27- fold, respectively, and after acute regimens, that of CYP3A by approximately 1.8-fold. 13C also increased activity of CYP2B up to 100-fold. Overall hepatic metabolism of E2 and E1, which was approximately 2-fold greater at 55 than 155 days of age, was increased (approximately 2.8-fold) by 13C with 2-, 4-, 16alpha-, 6alpha-, 6beta-, and 15alpha-hydroxy (OH) comprising > or = 54, 3, 2, approximately 2, approximately 5, 7, and 2%, respectively, of E1 and E2 metabolites. Acute regimens of beta-NF increased 2- and 15alpha-OH-E2 (62 and 5% of total) from E2 and 2-, 4-, and 6alpha-OH-E1 + 6beta-OH-E1 (32, 13, and 4% of total) from E1. Mammary gland metabolized E2 to E1 and small amounts of 15alpha-, 4-, 16alpha-, 6beta-, and 6alpha-OH-E2. After the acute IC3 regimen, E2 was also converted to 2-OH-E2. 17Beta-HSD-catalyzed oxidation of E2 was favored in the liver and reduction of E1 was favored in mammary gland and tumor (= 1% of hepatic activity). An increased (approximately 2-fold) ratio of reductive to oxidative activities in malignant mammary tumors by chronic 13C regimen may stimulate tumor growth. This is the first report showing that after chronic oral regimens, the 13C-, but not beta-NF-, induced changes in CYP complement led to elevated E2 and E1 metabolism. The persistent effects of increased putative carcinogenic and estrogenic 4- and 16alpha-OH as well as 6alpha- and 6beta-OH-E2 and 6beta-OH-E1 might counteract those of the less estrogenic 2-OH metabolites, thus accounting for the lack of suppression of mammary tumorigenesis by 13C in our previous study. 相似文献
210.